Sandy had dreamed for years of her own grey mare. Then her parents decide to pack up their city lift and live on a farm - with stables! And when Fergus finds Mimosa at the horse sale, it seems as if all Sandy's dreams are coming true...

But Mimosa is uncontrollable - and if Sandy and Fergus cannot manage her, they will have to sell her. Why does she behave so badly? The answer comes as a complete shock...

And so does the dreadful discovery, one night, that the gates are open, and the field empty...